The present invention relates to the field of space vehicle systems and subsystems used for inertial measurements, guidance and control. Specifically, the present invention relates to such systems and subsystems employing fiber optic gyroscopes (FOGs) and control moment gyroscopes (CMGs). FOGs perform a function similar to a mechanical gyroscope, but operate based on the interference of light that passes through a coil of optical fiber. Because they require no moving parts, they are generally considered more reliable than mechanical gyroscopes and are commonly used in space applications as a result. CMGs are attitude control devices that consist of a spinning rotor and one or more motorized gimbals that tilt the rotor's angular momentum, thereby causing a torque that rotates the spacecraft.
It has historically been assumed in space vehicle design that all the antenna communications systems be placed externally and configured to provide signal paths into the satellite via cables, with the electronics systems occupying various subsystems within the vehicle. These electronics systems thus take up valuable space within the space vehicle. Most three-axis FOG inertial measurement units (IMU) consist of a single, standalone package containing all three fiber coils placed orthogonally, thereby providing three axes of rotation rate measurements. CMG torqueing systems for space vehicles also typically occupy standalone volumes dedicated to providing torque, often configured with several solid heavy metal torqueing wheels; these are spun-up and maintained at various rotational speeds and are rotated to apply torque in varying conditions, thus providing various torque values to the space vehicle for orientation. A key but previously unrecognized limitation to these standalone subsystem packaging paradigms is that the diameters are restricted to only the space provided solely for the FOG 3-axis IMUs and separate volumes for the CMG wheels and electronics. In addition, the inventor hereof has recognized that placing these components nearer to the center of the space vehicle reduces their sensitivity.
Given the great cost of launching satellites and other space vehicles into space and the premium attached to available volume within a space vehicle, a more efficient way to configure systems and subsystems associated with a space vehicle or satellite, particularly systems and subsystems related to FOGs and CMGs, would be highly desirable. In addition, a configuration of FOGs and CMGs that maximized the sensitivity of these instruments would also be highly desirable.
References mentioned in this background section are not admitted to be prior art with respect to the present invention.